The BOOST_PP_REPEAT_z macro represents a reentry into the BOOST_PP_REPEAT repetition construct.

Usage

BOOST_PP_REPEAT_ ## z(count, macro, data)

Arguments

z
The next available BOOST_PP_REPEAT dimension.
count
The number of repetitious calls to macro.  Valid values range from 0 to BOOST_PP_LIMIT_REPEAT.
macro
A ternary operation of the form macro(z, n, data).  This macro is expanded by BOOST_PP_REPEAT with the next available repetition depth, the current repetition number, and the auxiliary data argument. 
data
Auxiliary data passed to macro.

Remarks

This macro expands to the sequence:
macro(z, 0, data) macro(z, 1, data) ... macro(z, count - 1, data)
At certain times, it may be necessary to perform the concatenation with BOOST_PP_CAT rather than the preprocessor token-pasting operator.  This happens when the z value is a macro invocation itself.  It needs a delay to allow it to expand.  The syntax in such a scenario becomes:
BOOST_PP_CAT(BOOST_PP_REPEAT_, z)(count, macro, data)

See Also

Requirements

Header:  <boost/preprocessor/repetition/repeat.hpp>

Sample Code

#include <boost/preprocessor/arithmetic/inc.hpp>
#include <boost/preprocessor/punctuation/comma_if.hpp>
#include <boost/preprocessor/repetition/repeat.hpp>

#define TEXT(z, n, text) BOOST_PP_COMMA_IF(n) text

#define TEMPLATE(z, n, _) \
   BOOST_PP_COMMA_IF(n) \
   template< \
      BOOST_PP_REPEAT_ ## z( \
         BOOST_PP_INC(n), \
         TEXT, class \
      ) \
   > class T ## n \
   /**/

BOOST_PP_REPEAT(3, TEMPLATE, nil)
   /*
   expands to:
      template<class> class T0,
      template<class, class> class T1,
      template<class, class, class> class T2
   */

Copyright Housemarque Oy 2002
Copyright Paul Mensonides 2002

Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at www.boost.org/LICENSE_1_0.txt)